Faithful anaphase is ensured by Mis4, a sister chromatid cohesion molecule required in S phase and not destroyed in G1 phase

摘要: The loss of sister chromatid cohesion triggers anaphase spindle movement. budding yeast Mcd1/Scc1 protein, called cohesin, is required for associating chromatids, and proteins homologous to it exist in a variety eukaryotes. removed from chromosomes degrades G1. We show that the fission Mis4, which equal separation different molecule behaves independent cohesin conserved human. Its inactivation G1 results cell lethality S phase subsequent premature separation. Inactivation G2 leads death metaphase-anaphase progression but missegregation occurs only next round mitosis. Mis4 not essential condensation, nor does degrade Rather, associates with punctate fashion throughout cycle. mis4 mutants are hypersensitive hydroxyurea (HU) UV irradiation retain ability restrain cycle when damaged or sustaining block replication. mutation synthetic DNA ligase mutant. may form stable link between chromatids split rather than anaphase.